Microbial Population Succession in Alcoholic Beverages Produced from Some Tropical Fruits

ABSTRACT

In the present study, monoculture and mixed culture fermentation techniques were employed to produce certain alcoholic beverages from watermelon; watermelon-banana and watermelon-pineapple mixtures. Three yeast species, namely, Saccharomyces cerevisiae, Kleochera apicalata, Torulospora delbruckii and four bacterial species Leuconostoc oenos, Lactobacillus Sp, Micrococcus luteus and Streptococcus lactis were identified. The daily succession of these organisms in the various fermenting samples differed in cell mass and occurrence due to their different growth conditions and factors present. A higher bacterial load (3.9 ± 0.2 - 4.4± 0.3) log (cfu) ml^-1 than yeast (2.8 ± 00 - 4.6 ± 0.4) log (cfu) ml^-1 counts was observed in the mixed culture fermentation, while in the monoculture fermentation, a higher yeast load (4.3± 0.3-4.7±0.2) log (cfu) ml^-1 than bacterial loads (2.7±0.1-4.1±0.3) log (cfu) ml^-1 counts was recovered. These results reflected that monoculture-fermented beverages were of better quality as compared to the mixed culture fermented ones, and the monoculture-fermented beverage from watermelon-pineapple mixture was ranked as the best alcoholic beverage.